Background. Exposure to noise from mobile devices is suspected to affect hearing. Data are limited, particularly in less developed countries. We assessed noise levels from mobile phones and user audiometric status at University of Ibadan, Nigeria, in an initial cross-sectional study. Methods. Fifty-eight staff and 45 young adult students owning mobile phones were selected. A pretested questionnaire assessed demographics, phone attributes, and predominant ear used for making and receiving calls. Noise was measured in A-weighted decibels. Pure tone audiometry was conducted at varying frequencies. Statistics computed included Chi-square and t-tests. Results. Certain phone brands used by students were commonly reported. More utilized right ears to make or receive calls. Mean reported mobile phone use duration by students was years, lower than among staff, years ( ). There were differences in use of head phones (22.2%, 12.1%) and speakers (51.1%, 15.5%) by students and staff, respectively ( ). Mean measured noise levels of phones when ringing, per user settings, were high ？dBA (students) and ？dBA (staff). Audiometry suggested 22.2% students and 28.0% staff had some evidence of hearing impairment. Conclusions. Mobile phones noise levels were high, but exposures though frequent were of short duration. Larger, longitudinal studies are needed on phone use and hearing impairment. 1. Introduction In general, less developed countries are establishing mobile (cellular) phone technology in preference to the traditional, and relatively more expensive, fixed line systems. Therefore, if there are any adverse health risks—potential biological effects—due to acute, repeated (or chronic) personal exposure to radiofrequency radiation from the use of mobile phones, then it will be a global concern; small impacts could have important public health consequences. This may be particularly true among younger adults using mobile phones for calls, music, e-mail, and so forth. According to WHO [1] and Nelson et al. [2], global prevalence of disabling hearing loss in adults was 16%, which may vary from 7% to 21% in various subregions of the world, and was attributable mainly due to occupational noise. However, with approximately four billion users of mobile phones worldwide [3], and with a significant proportion incorporating media playing capability and speakers, mobile phones are among the most popular portable media players (PMP) on the market and present an emerging health concern in both occupational and nonoccupational settings. Ear pieces, as mobile phone accessories, and most
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